Ototoxic effect of n-hexane and ethylbenzene in persons occupationally exposed to volatile organic compounds mixtures (VOC)

Abstract

Some volatile organic compounds (VOCs) have shown ototoxic potential in occupational as well as in experimental exposures. This research evaluated preclinical signs of ototoxicity in people occupationally exposed to a VOCs mixture. The auditory function using auditory evoked potentials of the brain stem was also evaluated, and individual levels of exposure to VOCs and their urinary metabolites were measured in people exposed to VOCs and a control group. It was observed that the mean latency of the wave V and intervals I-III and I-V at 70 dB of stimulation was higher in exposed group (p < 0.01; p = 0.01 and p = 0.02, respectively). Also a positive correlation between levels of exposure to n-hexane and I-III interval was found (r = 0.62, p = 0.02); for ethylbenzene levels, a strong trend was found for a positive correlation r = 0.54, p = 0.05). These results show auditory central pathway damage secondary to ethylbenzene and n-hexane exposure in persons exposed to mixtures of  VOCs.